Cylinder block

ABSTRACT

A two-stroke internal combustion engine has cylinders in two planes offset from each other at 90*, a bore to contain a crankshaft is provided adjacent the inner ends of the cylinders and at right angles thereto, and a bore is provided within the included angle parallel to the crankshaft bore constituting a valve cylinder which has ports for supplying air or fuel and air to the cylinders.

United States Patent 1191 Squelch Jan. 8, 1974 CYLINDER BLOCK 2,018,914 10/1935 Endres 123/65 B 1,690,321 11/1928 Baher 123/65 VC [761 Invent: Edward squelch 243 1,048,760 12 1912 Taff 123/65 vc Greenfern -1 Slough, England 3,471,079 10/1969 Myers 417/403 [22] Filed Mar 4 1971 3,228,195 1/1966 Brent et a1. 60/54.6 A

[21] Appl. No.: 120,848 Primary Examiner-Martin P. Schwadron Assistant Examiner-A. M. Zupcic Related U.S. Application Data [63] Continuation-impart of Ser. No. 808,798, March 20, Attorney wllham A Drucker 1969, b d d.

a 57 ABSTRACT [52] U.S. C1. 123/65 B, 417/399, 417/511 A r ke internal combustion engin h cylinders [51] Int. Cl. F02d 39/04, F04]; 17/00, F041;, 7/00 in two planes offset from each other at 90, a bore to [58] Field of Search 123/65 B, 65 VC; in a r nkshaft is provided adjacent the inner 417/345, 346,- 347, 403, 404, 511, 397, 399 ends of the cylinders and at right angles thereto, and a bore is provided within the included angle parallel to [56] Refer n Cit d the crankshaft bore constituting a valve cylinder UNITED STATES PATENTS vyhich has ports for supplying air or fuel and air to the 1,100,279 6/1914 Dean 123/65 B cylmders' 1,916,043 6/1933 Enright 123/65 B 2 Claims, 10 Drawing Figures 56 -":it 59 17 L 3 V 57 IZ 1 1 43 /A\/ 5 4 1 i 27" I T 1 I H l 1 12' s c 1 1 1'1 F 1 I 1 1 1 l D E L 64 tL L.L c: 1 1

PATENTED JAN 8 SHEEI 1 0F 7 CYLINDER BLOCK This is a continuation-in-part of application Ser. No. 808,798, filed Mar. 20, 1969, now abandoned.

This invention relates to four or eight cylinder twostroke internal combustion engines and its main object is to provide a two-stroke engine of compact size and shape which does not require lubricating oil to be mixed with the petrol whereby a cleaner exhaust is achieved.

According to the present invention I provide improvements in a two-stroke internal combustion engine having four cylinders, wherein the axes of the cylinders are in two planes offset from each other with an included angle less than 120a crank-shaft bore to contain a crankshaft adjacent the inner ends-of the cylinders and at right angles to the cylinder axes, a valve bore within the included angle parallel to the crankshaft bore, an air-fuel valve and compressor device in said valve bore, ports in said bore for supplying compressed air-fuel mixture to the cylinders, and a carburettor supplying air-fuel mixture to said valve bore.

The inlet valve may consist of a valve piston sliding within the valve cylinder and operated by an actuating member which is reciprocated by fluid pressure.

The valve piston may, for example, in a four cylinder engine supply fuel-air mixture to two ports for two cylinders at one end of the valve cylinder when moving towards that end and supply fuel-air mixture to two other parts at the other end of the cylinder when moving towards said other end.

A constructional form of the invention will now be described by way of example with reference to the accompanying diagrammatic drawings wherein:

FIG. 1 is an elevational view of the main parts of an engine housing made in accordance with the invention;

FIG. 2 is a half sectional view on the line 2-2 on FIG. 1 (with part of the other half);

FIG. 2A is a similar view of the other end of the parts shown in FIG. 2;

FIG. 3 is a half sectional view, on line 33 on FIG. I;

FIG. 3A is a similar view of the other end of the parts shown in FIG. 3;

FIG. 4 is a view similar to FIG. 1 but showing the opposite end of the engine;

FIGS. 5, 6, and 7 are details of a pump to be described; and

FIIG. 8 is a view of an exhaust valve device.

The engine housing may be made as a single casting or if preferred it may be built up from two or more parts. As shown it is made up by a series of plates 9 shaped A B C F G H I L M with spacers between them. It is formed with two cylinders 12 in line only one of which is shown as the other cylinder is behind the one shown in FIG. 1. The cylinders 12 are offset 90 from two further in line cylinders 13. The inner ends of the cylinders 12 is shown at D, E and the inner ends of cylinders 13 is shown at J, K. The housing has a bore 15 to contain the crankshaft 16 on a centre line at the intersection of the centre lines of the cylinders 12, 13. Within the included angle of 90 the housing is formed with a pump bore 17 which contains the inlet valve for supplying fuel-air mixture to the four cylinders. This bore is equidistant from the cylinders 12, 13. The crankshaft may be formed in separate pieces, e.g. four pieces as shown in FIG. 2. Bearings are provided at 22, 23, 24 and a thrust washer at 25. Crank pins shown at 2 28, 29 each carry two connecting rods 27 (FIG. 1 but omitted from FIG. 2) for the cylinders 12, 13. Crankshaft webs are shown at 30, 31, 30A, 31A.

The crankshaft carries a sprocket-32 centrally which drives an output shaft 33 by means of a chain 34 and sprocket 35.

An inlet port 41 is provided in the pump bore 17 which also has ports 42, 43 at each end leading to the cylinders. These four ports 42, 43 are controlled by two cylindrical hollow pistons 45, 45A which slidably fit in the bore 17. The ports 42, 43 at one end of the bore 17 supply air-fuel mixture to the cylinders 12 and the similar ports 42, 43 at the other end of the bore 17 supply air-fuel mixture to the cylinders 13.

These pistons are connected together connections 69 so as to be reciprocated by a reciprocable actuating member 46 which is reciprocated by a pair of rams 47, 47A which are both fixed to the member 46. The rams extend from the member 46 in opposite directions and are reciprocated by oil pressure supplied through ports 71 (FIG. 3) and 71A (FIG. 3A). It will be understood from FIG. 3 that a port 71 is provided in a plate 72 at that end and from FIG. 3A it can be seen that at the other end there is provided a pump and valve device 75 (FIGS. 3A and 4 to 7).

The rams 47 and 47A operate in fixed cylinders 48, 48A located within the pistons 45, 45A and supplied with oil at pressure through the ports 71, 71A, and the pump and valve device 75 directs oil under pressure alternately to the two rams and exhausts the ram not under pressure. A gap 50 is provided between member 46 and piston and a similar gap is provided between member 46 and piston 45A. These gaps provide a dwell or floating action when reversing the motion of the piston.

A carburettor 54 is connected to the bore 17 by means of the port 41.

The pump and valve device is bolted to one end of the engine housing as shown in FIG. 4 and consists of a fixed plate 76 (FIGS. 3A and 6) containing the port 71A spaced from a fixed plate 78 formed with a double ended pump chamber 79 having a port 71C connected by pipe 71B at one end of the pump chamber to the port 71. Between the plates 76, 78 is a reciprocatory frame 80 which is reciprocated by an eccentric 81 (FIGS. 2A and 5) fixed on the. end of the crankshaft. The frame 80 carries a block 83 which serves as a pump piston and oscillates in the 'pump chamber 79. The plate 78 has inlet ports 84, 85 supplied with oil under pressure for making up any lost oil. The frame 80 has oil grooves 86, 87 which match up with ports 84, 85. When the block 83 moves towards one end of its stroke oil is forced out of one end of the chamber 79 through pipe 71B into port 71 and when the block 83 moves in the other direction oil is forced out of the other end of the chamber into the port 71A. Thus rams 47, 47A are shuttled back and forth continuously thereby reciprocating the member 46 which 'drives the pistons 45, 45A in alternate directions.

When the pistons 45, 45A are moving left to right (FIG. 3) the pressure in the left hand end of pump cylinder 17 tends to be reduced and therefore combustion mixture enters at port 41 which is in communication with ports 42, 43 through the gap 50 and through the hollow piston 45. When the pistons start moving right to left the gap 50 is closed and the mixture is compressed and eventually is fed to two of the engine cylinders through ports 42, 43 while mixture enters at port 41 to the right hand end of the cylinder 17 through the other gap 50 which is now open.

Thus no fuel enters the crank case so there is no difficulty about lubricating oil to the petrol. Therefore of course no other blower or compressor is required for compressing the air-fuel mixture in the crank case, and exhaust gases are much cleaner than when oil is mixed with petrol.

When the block 83 is at one end of its stroke makeup oil enters pump space 79 via ports 84, 86 and at the other end of its stroke makeup oil enters via ports 85, 87.

This simple pump and valve device is merely shown by way of example as any other such device may be used which will alternately supply oil to and exhaust oil from the ports 71, 71A.

Each end of the bore receives a cylindrical valve housing 51 (FIG. 2) containing two cylinder exhaust valve operating means 52. The exhaust valve is shown at 60 in FIGS. 1 and 8.

An exhaust valve tappet housing 90 has a cylindrical outer periphery 91 which fits a bore in the engine block 9. The housing is ring-shaped and its inner cylindrical periphery 92 is of large enough diameter to receive a cam 93 fixed on the crankshaft 16. The housing has outwardly extending or radial bores 96, 97 offset 90 from each other and containing tappets 98, 99. The tappets have heads 101, 102 within the housing engaging the cam.

The tappet 99 has a semi-spherical depression 105 in its outer end engaged by a rod 106 the other end ofwhich engages a ball 107 which engages a seat in a rocking lever 110. The lever 110 is pivoted at one end at 111 and its other end actuates the stem of the exhaust valve 60. The rocking lever is provided with a return spring not shown. The tappet 98 operates another exhaust valve through similar means not shown.

A similar two-valve operating system may be provided in the bore at the other end of the crankshaft.

The housing 90 also has an outwardly extending or radial bore containing a relief valve 114 which controls the pressure of oil within the housing 90.

A bore 115 receives oil for lubrication.

The combustion space is shown at 61 and the sparking plug will be located at 62. The cylinder heads 63 are bolted by bolts 64 to spacers between the plates 9.

The pistons 59 will be longer than the stroke and have as perfect as sealing as possible.

A modification of a Solex 2 choke carburettor may be provided at 54. The secondary choke may be linked to a vacuum diaphragm which in turn is connected to a port 72 in the bore 17 between the two pistons 45.

Auxiliary drive means for the oil pump, distributor and water pump are arranged to be driven at the front end of the crankshaft, e.g. by chain or belt drives.

A starter motor 56 is mounted on a cradle 57 fixed on the plates 9. Ducts such as 116 (FIG. 3.) are provided where necessary for lubrication.

I claim:

1. A two-stroke internal combustion engine having four cylinders the axes of which are in two planes offset from each other with an included angle less than 120a bore to contain a crankshaft adjacent the inner ends of the cylinders and at right angles to the cylinder axes, and a pump bore within the included angle parallel to the crankshaft bore, an air fuel valve or pump device in said pump bore, ports in said pump bore for supplying compressed air-fuel mixture to the cylinders, a carburettor supplying air-fuel mixture to said pump bore, said air-fuel pump comprising two hollow pistons sliding in said pump bore, an actuating member located between them and alternately spaced from the pistons and opening and closing the adjacent ends of the pistons whereby air-fuel mixture is caused to enter into the pump bore from the carburettor, the air-fuel mixture entering each piston in turn while open while the closed piston compresses a charge therein, two cylinders located in the pump bore one at each end thereof, two rams located in said cylinders respectively, said rams being connected to said actuating member, and means for alternately supplying liquid under pressure to said cylinders and exhausting pressure therefrom to reciprocate the rams which in turn reciprocate said pistons.

2. An air fuel valve device for an internal combustion engine comprises a housing having a pump bore, two hollow pistons sliding in said pump bore, an actuating member located between them and alternately spaced from the pistons and opening and closing the adjacent end of the pistons whereby air-fuel mixture is caused to enter into the pump bore by the pistons, the air-fuel mixture being drawn in by the open piston while the closed piston compresses a charge, two cylinders located in the pump bore one at each end thereof, two rams located in said cylinders respectively, said rams being connected to said actuating member, and for alternately supplying liquid under pressure to said cylinders and exhausting pressure therefrom to reciprocate the rams which in turn reciprocate said pistons. 

1. A two-stroke internal combustion engine having four cylinders the axes of which are in two planes offset from each other with an included angle less than 120a bore to contain a crankshaft adjacent the inner ends of the cylinders and at right angles to the cylinder axes, and a pump bore within the included angle parallel to the crankshaft bore, an air fuel valve or pump device in said pump bore, ports in said pump bore for supplying compressed air-fuel mixture to the cylinders, a carburettor supplying air-fuel mixture to said pump bore, said air-fuel pump comprising two hollow pistons sliding in said pump bore, an actuating member located between them and alternately spaced from the pistons and opening and closing the adjacent ends of the pistons whereby air-fuel mixture is caused to enter into the pump bore from the carburettor, the air-fuel mixture entering each piston in turn while open while the closed piston compresses a charge therein, two cylinders located in the pump bore one at each end thereof, two rams located in said cylinders respectively, said rams being connected to said actuating member, and means for alternately supplying liquid under prEssure to said cylinders and exhausting pressure therefrom to reciprocate the rams which in turn reciprocate said pistons.
 2. An air fuel valve device for an internal combustion engine comprises a housing having a pump bore, two hollow pistons sliding in said pump bore, an actuating member located between them and alternately spaced from the pistons and opening and closing the adjacent end of the pistons whereby air-fuel mixture is caused to enter into the pump bore by the pistons, the air-fuel mixture being drawn in by the open piston while the closed piston compresses a charge, two cylinders located in the pump bore one at each end thereof, two rams located in said cylinders respectively, said rams being connected to said actuating member, and for alternately supplying liquid under pressure to said cylinders and exhausting pressure therefrom to reciprocate the rams which in turn reciprocate said pistons. 